In the darkest and coldest parts of its polar regions, a team of scientists has directly observed definitive evidence of water ice on the Moon's surface. These ice deposits are patchily distributed and could possibly be ancient. ...

Glacial retreat in the Canadian Arctic has uncovered landscapes that haven't been ice-free in more than 40,000 years and the region may be experiencing its warmest century in 115,000 years, new University of Colorado Boulder ...

Between 1995 and 2003, NASA's Galileo spacecraft made several flybys of Jupiter's moon, Europa. Several findings from observations of the moon pointed to evidence of a liquid ocean beneath Europa's icy surface. The ocean, ...

A pair of researchers, one with the Woods Hole Oceanographic Institution, the other Harvard University, has found evidence of deep ocean cooling that is likely due to the Little Ice Age. In their paper published in the journal ...

A survey of ice in Greenland has uncovered evidence suggesting a kilometer-wide iron asteroid slammed into that island, perhaps as recently as 12,000 years ago during the end of the Pleistocene. The resulting 19-mile-wide ...

Over the last 540 million years, the Earth has weathered three major ice ages—periods during which global temperatures plummeted, producing extensive ice sheets and glaciers that have stretched beyond the polar caps.

Ice

Ice is a solid phase, usually crystalline, of a non-metallic substance that is liquid or gas at room temperature, such as carbon dioxide ice (dry ice), ammonia ice, or methane ice. However, the predominant use of the term ice is for water ice, technically restricted to one of the 15 known crystalline phases of water. In non-scientific contexts, the term usually means ice Ih, which is known to be the most abundant of these solid phases. It can appear transparent or opaque bluish-white colour, depending on the presence of impurities or air inclusions. The addition of other materials such as soil may further alter the appearance.

The most common phase transition to ice Ih occurs when liquid water is cooled below 0°C (273.15K, 32°F) at standard atmospheric pressure. It can also deposit from vapour with no intervening liquid phase, such as in the formation of frost.

Ice appears in nature in forms as varied as snowflakes, hail, icicles, glaciers, pack ice, and entire polar ice caps. It is an important component of the global climate, and plays an important role of the water cycle. Furthermore, ice has numerous cultural applications, from ice cooling of drinks to winter sports and the art of (ice sculpting).

The word is derived from Old English ís, which in turn stems from Proto-Germanic *isaz.